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By W. M. Armstrong

THE GROWTH of the major iron and steel industries on this continent and in many European countries was based on the use of as-mined, high-grade, lump iron ores and on the availability of metallurgical coking coals. The modern coke-fired blast furnace was developed for such materials and is one of the most efficient of ail pyrometallurgical processes. Most of the impure pig iron produced by blast furnaces was converted to refined steel by the Bessemer process in the years prior to 1900 but, when large quantities of low-cost steel scrap be-came available, the more flexible open hearth process was adopted by most large steel producers on this continent. Although this pro-cess has many desirable metallurgical features, the thermal efficiency is low, the capital cost is very high, and the method of charging scrap steel is inefficient by modern standards of material handling. In recent years several conditions have arisen which have stimulated the development of many new pro-cesses and the re-examination of the existing smelting and steelmaking techniques.

Jan 1, 1958

By Alan Jessop

A small group has been set up at the Dominion Observatory, Ottawa, to make a survey of terrestrial heat flow throughout Canada. Terrestrial heat flow is the heat rising from the interior of the earth and escaping at the surface, and is calculated from a knowledge of under-ground temperature distribution and the thermal conductivity of rocks. A small number of diamond drill holes are being sunk for the purpose of measuring temperatures below the surface, but the program is inadequate for a thorough survey. Mines and holes drilled for other purposes are being sought by the Dominion Observatory group to supplement their own drilling program. F ROM January, 1.962, to December, 1964, geo-physicists of many nations will be cooperating in the "International Upper Mantle Project." Unlike tl1e International Geophysical Year, which was mainly concerned with the fluid layers surrounding the earth, the Upper Mantle Project is an intensive study of the solid earth. Canada, with its large land area and extensive Precambrian Shield, is an active participant in the project.

Jan 1, 1964

By V. Polotski

This paper describes a platform for autonomous operations in open pit mining environments. A typical operation consists of: (1) Initial locomotion toward a remote worksite; (2) Pattern navigation within the worksite; (3) Worksite manipulations and (4) Return locomotion to the start location. The platform includes precise localization module based upon the fusion of odometry, inertial and GPS measurements. The guidance module starts from a set of way points specified on a GPSreferenced map and plans and executes the mission. A typical mission includes specified manipulative tasks along the navigation path. During motion execution the on-board system continuously verifies that the path is free of obstacles and that the hardware is not overloaded. Momentary losses of external positioning measurements does not adversely affect the performance, owing to the redundancy in position and heading estimation. A rehearsal phase follows planning and allows the supervisor to examine the kinematic behavior of the platform during motion, thus reducing the need for continuous monitoring during execution and providing protection against potential losses of communication.

May 1, 2003

By Wenxue Chen

This paper presents a new type of bolt with full thread and uniform strength, and fabricated with a Glass Fiber Reinforced Polymer (GFRP) bolt-making machine designed by the authors. The mechanical performance of the new bolt is assessed with strength tests conducted with the bolt in acid, alkaline and saline water conditions, with increasing concentration. The purpose is to test the new GFRP bolt?s mechanical performance in harsh conditions, especially metal mines with acid or alkaline environments. Comparison of the color, weight, size and antistatic ability of the GFRP bolt before and after it is immersion in solution is presented. Changes in tensile and shear strength, torsion, and anchoring force were evaluated in the laboratory. The results show that the mechanical properties of the GFRP bolt are more sensitive in alkaline than in acid and saline water. However, the loss ratio of mechanical properties of the GFRP bolt is very small according to the results of tensile and shear strength, torsion and anchoring force. The new bolt can be useful for applications in acid or other harsh mines.

Aug 1, 2013

By W. P. Clement, M. C. Bell

"PT International Nickel Indonesia, a subsidiary of Inco Limited, mines and processes nickel laterite ores for the supply of nickel matte, primarily to the Japanese market. It has large ore reserves and a substantial portion of its energy requirement is supplied from its own hydro-electric plant. Since the early 1980s, the company has increased its production level and has dramatically reduced its unit costs. Projects are in progress to further decrease costs and recently a major expansion - 31% increase in nominal capacity - has been undertaken, consistent with marketing opportunity in Japan. The expansion project, which has a low capital cost per unit of production, is outlined in this paper.IntroductionPT Inco is a fully integrated mining and smelting facility located in Indonesia on the island of Sulawesi, and is based on a very large, world class nickel laterite orebody located 60 km inland from the Gulf of Bone. Construction of a single furnace line plant started in 1973. Complete supporting infrastructure of townsite, hospital, schools, shopping centres, road systems, and an airport, all had to be built. Prior to completing the first phase, the decision to expand the plant to a three kiln-furnace line was made. A major factor in the decision was the ability to develop the hydroelectric potential of the nearby Larona River. This involved construction of a 30 m high dam, and a 7 km surface canal to the generating station. The penstocks drop 150m to three 55 Mw turbines. The power generated is sufficient to supply the entire electrical load for the complete smelting complex and town site. The unique capability to supply the high smelting energy requirements for a lateritic nickel ore by fully captive hydro power, has, over the past decade insulated PT Inco from the large upward swings in oil prices suffered by other lateritic nickel producers.Wet ore is first partially dried to 20% moisture in two co-currently fired rotary driers, screened on an internal trommel, and delivered to two dry ore storage buildings. The partially dried ore is calcined at 750°C and partially reduced in three large 100 m by 5.5 m kilns. Reduction is accomplished by lancing bunker C oil onto the ore bed at the discharge end of the kiln. The kilns are equipped with five air pipes with onboard blowers to gradually bum the combustible gases generated by the lance oil. The kilns were also originally equipped with two side burners to supply additional heat close to the feed end of the kiln. Calcined ore is transferred by 20 ton refractory lined containers to the furnace feed bins at the top of the smelter. Smelting is carried out in three 18 m diameter furnaces powered by 45 Mw transformers. Slag is skimmed at 1550°C through water cooled breast plates and removed to the slag dump by Haulmaster Carriers. Matte of 25% Ni, 1O% S, 65% Fe is tapped at 1350°C into the converter aisle. The iron is slagged in converters to produce a nickel sulphide matte at 80% Ni. Three rotary Kaldo converters were initially installed. The product matte is granulated, dried, and shipped in returnable rubber bags to Japan. Most of the matte is fluid-bed roasted to nickel oxide and then directly reduced in a second reducing fluid bed reactor at our facilities in Japan.The smelting complex was designed to smelt two million tonnes of dry ore per year, equivalent to 34 000 tonne nickel production at an ore grade of 2% Ni. The cost of the entire project including working capital was $900 million."

Jan 1, 1990

By Gilles Bonin

Structures and serpentinization patterns in the Thetford Mines peridotites are important characteristics indicating the necessary geological conditions which led to the development of chrysotile orebodies in Early Ordovician limes. These structures and serpentinization patterns are reviewed in this paper using the geology of LAB Chrysotile orebodies as a model. Structural aspects include parallel and transverse faults, parallel and transverse granite slabs, and orebodies, some of which trend clearly north-westward parallel to the accretionarymovement. Serpentinization patterns in the peridotite belt, particularly in the harzburgite, include primary pervasive mass serpentinization and secondary complete serpentinization. Listwaenites layers appeared along some faults and along some granite slabs as a result of hydrothermal alteration of the serpentine, following the emplacement of the devonian plutons to the south. These plutons as we/1 as other important lineaments, align with the structural pattern of Thetford Mines ophiolites. It is believed that these plutons are part of a heavy magma tic corridor resembling the Pilote-Mont-Louis corridor in the Gaspe (Doyon and Berger, 1997), and the Buchans' structure in Newfoundland (Hutchinson, 1984), both intersecting the Brompton-Baie Verte line.

Jan 1, 2001

By J. Ran

"Hangingwall sloughing is the major cause of unplanned stope dilution in open stope mining. Understanding the hangingwall sloughing mechanism can guide the stope design in minimizing the unplanned dilution and improving muck size and therefore mining efficiency. Though the modified stability graph method may be adopted to assess the hangingwall stability, for mines where the hangingwall is inaccessible, the required parameters are difficult to define and some of the simple influential factors cannot be easily identified in this method to provide guidelines for stope design.This paper identifies the main modes of hangingwall sloughing in open stope mining based on detailed data collected from mined-out stopes and site observations, applies the voussoir beam notation to analysis of the hangingwall sloughing mechanism, compares the model analysis results with the collected stope data, and provides guidelines for stope design and model application. Finally, examples are given to demonstrate the time and support effects on hangingwall sloughing and stope dilution."

Jan 1, 2002

By . A. C. Atenas

Control of arsenic in the Potrerillos' Refinery electrolyte has been obtained by withdrawing a bleed stream of circulating electrolyte and ensuring the ratio of [O]/[As] in the cast anodes is maintained between 0.9 and 1.0. In order to achieve this control the anode oxygen must be adjusted, depending on the arsenic level in the cast anodes. It has been necessary to modify the time of the reduction step in the anode furnace refining process. Control of this ratio has permitted electro refining of anodes with high levels of arsenic, up to 3000 ppm, while minimizing the volume of electrolyte that must be removed for impurity control so as not to affect the copper concentration in the electrolyte. However this control strategy is not useful when the arsenic concentration in the cast anode is too high, because it is limited by the maximum oxygen concentration allowable for a good quality anodic. Costs have been reduced in anode furnace refining because it is no longer necessary to use alkaline flux injection to remove the arsenic in cast anodes.

Jan 1, 2007

By MKS Vel, S. Mukhopadhyay, R. Mishra

Off late, the criteria of selecting the refractory have acquired a trend line aiming to a cleaner environment and the utmost importance is given to the eco-friendly approach. The stainless steel making furnaces normally use mag-chrome refractories for the obvious reasons of changing slag basicity from acidic to basic. Such refractories generate toxic fumes and compounds with hexavalent chrome, which is unhygienic if inhaled. The present paper describes the development of a chrome free alumina magnesia carbon refractory, it's different test properties, simulative testing and microstructures. The optimum quantity and distribution of carbon in the brick restricts the carbon pick-up by the steel. Bricks with the same composition were manufactured in the commercial scale and used in a stainless steel making furnaces in USA. The performance of same refractory in this furnace was quite encouraging and at present the same quality brick has become a normal practice in this furnace. Since no chromite is used in making this brick, so no toxic compounds are generated environment remains pollution free.

Jan 1, 2004

By G. B. Harris

A new process for the recovery of copper and associated base metals from a polymetallic massive sulphide ore is described. The massive sulphide contains copper and especially nickel sulphide in a mineralogical form which negates both good recovery and high grades in concentrates using conventional flotation methods. Flotation concentrate processing and smelting from this ore is therefore probably not an economically viable option. Utilising the properties of high concentration chloride brines, a flow sheet has been developed and tested whereby the recovery of all of the metals and some of the power requirements for the plant itself can be derived from the ore. The new process overcomes the less-amenable-to-flotation ore characteristics, and provides the opportunity of economic processing in remote locations where the dependency on fossil fuels is both a logistical and an economic concern. The Ferguson Lake deposit of Starfield Resources in Nunavut, Canada, is the subject of this paper, which focuses on the leaching and copper recovery unit operations of the proposed flow sheet.

Jan 1, 2007

By P. Carlone, A. Astarita, F. Rubino

Cold gas dynamic spray is an innovative technology allowing the deposition of thin metallic layers on a bulk or sheet substrate. Titanium on aluminum deposition is very attractive to the aeronautic industry, due to the enhanced corrosion resistance and wear properties of titanium coating as well as its improved compatibility with CFRP, preserving the reduced cost of aluminum substrate. One main drawback, however, is related to the micro-porosity of the deposed layer, negatively affecting the corrosion barrier performance. In this paper, the effect of selective laser post-treatment on pure grade 2 titanium coatings on AA2020-T3 sheets was experimentally and numerically investigated. Morphological features, microstructure and chemical composition of the treated zone were assessed by means of optical microscopy, scanning electron microscopy and energy dispersive X-ray spectrometry. Microhardness measurements were also carried out to evaluate the mechanical properties of the treated coating. A numerical model of the laser treatment, based on a finite volume scheme, was implemented and solved to simulate the process and discuss the experimental outcomes. Obtained results highlighted the key role played by heat input and dimensional features on the effectiveness of the treatment.

Jan 1, 2015

By H. L. Cameron

Introduction Since the beginning of gold mining in Nova Scotia in the year 1860, the biggest problem o the mine operators has been to find and follow the ore zones in the narrow quartz veins. It was early recognized that all veins were not gold bearing and that, in those that were, the commercial ore was confined to limited zones. A large number of geologists and mining engineers have been interested enough to give time and thought to the problem, but, until the last four or five years preceding World War II, they were handicapped by lack of exact data from mining operations. The necessary data could only be obtained by daily checking of underground operations. Such daily checks were instituted at a number of mines during the period 1935-40 and, in every case, were successful in delimiting the ore zone or zones for the particular mine. The present paper deals with the results of this work as applied to practical ore finding. It is an attempt at extrapolation, from observations in the four districts with which the writer is personally familiar, co other districts in which similar conditions or structures are reported.

Jan 1, 1947

By Kosei Ishida

To achieve renovation work without noise, the authors developed techniques of manufacturing pre-cut interior finishing components for renovation work. In this paper, to achieve the system of pre-cut interior finishing components, the authors describe a measuring method of reinforced-concrete structure by 3D laser scanner and then describe a method of making a design of pre-cut interior finishing components with the polygon model. Using these two methods, the steps of manufacturing pre-cut interior finishing components consist of the following four steps: First, measure the building shape using a 3D laser scanner. Secondly, integrate a point cloud data and retrieve the markings on the floor. Then, create a polygon model of the building based on the point cloud data. Lastly, make a drywall design using a polygon model. To evaluate the technique feasibility of manufacturing pre-cut interior finishing components, the authors have conducted an experiment of the finishing interior work of the drywall. Using pre-cut interior finishing components, the authors have been able to achieve interior finishing work without noise.

Aug 1, 2013

By F. K. McKean

THE task of establishing a new corrosion testing laboratory is more difficult than it need be because there is very little information on the subject available in the literature. Many articles describing tests and results may be found, but a wide search will unearth only passing remarks on the different types of equipment that may be selected for accelerated corrosion tests. An article describing some of the apparatus needed in a corrosion laboratory should be of help to those interested in building a new unit or in making additions to an old one. In May of this year, the writer was given the assignment of equipping a laboratory for general corrosion testing, to form a part of the new Physical Metallurgy Research Laboratories of the Department of Mines and Resource~ at Ottawa. With the help of senior members of the staff, along with what could be gathered from other sources, a list of necessary equipment was compiled and a plan for arranging it in the rooms was decided upon. Where possible, the apparatus was constructed in the excellent machine shops at the disposal of this Department, while the rest was placed on order with the manufacturers.

Jan 1, 1945

By J. A. Hansuld

"THIS SESSION marks something of a milestone in that it is, as far as I know, the first session at a CIM Annual Meeting devoted entirely to exploration geochemistry. This is an indication of the general acceptance and widespread recognition by industry of geochemistry in mineral exploration. As a first, I hope it proves sufficiently successful and interesting that geochemical exploration sessions will become a routine part of future CIM annual meetings. The greater use and acceptance of geochemistry has resulted in many investigations and advances, especially in areas such as the Canadian Shield. For a first session on geochemistry, the meeting in Quebec suggested an ideal opportunity to assess these advances and report on the current application of geochemistry in the Shield. The theme of the session is ""Geochemical Exploration in the Canadian Shield - The State of the Art."" A series of six papers will be presented dealing with the various dispersion media - rocks, heavy minerals, ""soils"", lake sediments, waters and vegetation. As a background to the individual presentations, I would like to take a few minutes to briefly trace the history of the use of geochemistry in the Canadian Shield."

Jan 1, 1971

By J. Sugai

Formability of extruded round AZ31 magnesium alloy tubes with different manganese concentrations was evaluated by performing bending tests and measuring strain along the length of the tubes during the bending process. It was found that an increase in the manganese content from 0.3 % to 0.7% did not exert any significant effect on the values of yield stress, elongation, or compression to fracture. However the hardness tended to increase and the UTS decreased. The compressive ductility was significantly lower than tensile ductility for all manganese concentrations. Consequently, the formability of tubes decreased, causing cracks in areas where compression strain occurred during bending. It was also found that a larger strain occurred in the latter half of the region along the length of tube between the clamp-end and the tube-positioning block. Within this region, alloy tubes with higher manganese concentrations, 0.5 and 0.7 %, there was a clear strain peak within the strain profile, while for the 0.3 % Mn alloy, a more uniform strain profile was exhibited, indicating a more uniform deformation. This was confirmed by microstructural analysis of the specimens.

Jan 1, 2006

By S. Kelebek, Gerhard W. Heinrich, Peter F. Wells

"The review and optimization of process stages is an integral part of the program to improve the metallurgical performance of the Strathcona Mill. Improved primary grind size distributions, streamlining of rougher-scavenger circuits and increased platinum recoveries were the target of plant and laboratory scale tests. The results can be summarized as follows:• Decreasing the primary grinding cyclone vortex finder diameter for nickel/copper ore gave significant increases in overall copper recovery and improved rougher flotation selectivity.• The scavenger flotation stage in the circuit treating copper ore was found to contribute little to this circuit's copper recoveries -yet to be essential for acceptable recoveries of nickel, platinum and gold. The elimination of this stage by re-routing the tailings from the copper ore rougher into the nickel/copper ore rougher feed has lead to lower gangue recoveries to the nickel concentrate and to improved copper-nickel separation, while reducing equipment operating costs.• Surface aging effects such as oxidation are known to decrease flotation recoveries of platinum minerals such as sperrylite. The conditioning of an intermediate non-magnetic process stream with copper sulphate prior to thickening increased the platinum recoveries in the subsequent flotation stage by approximately 10%."

Jan 1, 1996

By K. G. Markkola

Since 2005, Compafifa Contractual Minera Candelaria (CCMC) has defined various strategies which aim to optimize the usage of the available energy in each of the SAG grinding circuit modules (SABC-A configuration). For this purpose, the use of larger size balls along with operating with an optimum balls/load ratio has been implemented. Additionally, in the ball mills, the amount of balls in relation to the equipment's usable diameter has been optimized. In the pebble crushing circuit, the percentage of material passing 12 mm (112 in) product has been increased by 15% by: (1) modifying the crusher mantle profile, (2) implementing a strategy for maximizing the power in each crusher, (3) using continuous improvement tools (Lean - Six Sigma), (4) redesigning SAG mills discharge grates, and (5) changing discharge grates in order to control the crusher feed size distribution profile. All these activities have improved plant throughput by 1,000 t/d with no significant capital investment. As part of the energy consumption optimization study, we have considered determining the optimum operational rate of each SAG mill, in relation to the mill liner life and also the improving the control strategy in conventional grinding.

Jan 1, 2007

By C. S. Lord

"The Regal Silver mine is 5 miles north-northwest of Albert canyon; a station on the main line of the Canadian Pacific railway; 21 miles east of Revelstoke; British Columbia.Development, commenced in 1918, comprises more than 8,000 feet of workings from six adits, one of which extends into the Regal Silver property from the adjacent Snowflake ground. Production has been limited to a little tungsten concentrate recovered recently from a few r..undred tons of ore treated in a small underground mill. The property has received some attention as a possible source of tin. The deposits are large quartz veins containing irregular sulphide bodies. Ore minerals normally make up less than 1 per cent of the veins and include pyrite, galena, sphalerite, scheelite, and stannite. The veins are approximately parallel with the bedding of the enclosing graphitic, siliceous to calcareous, slates and argillites. These strata are of Precambrian age, strike about northwest, and dip northeast. No other rocks are known in the vicinity of the workings . Granitic rocks, intrusive into t'he sediments, outcrop 4 miles to the southwest and 7 miles to the northeast and may underlie the property at no great depth."

Jan 1, 1954

By Abdelkabir Maqsoud

Different management options and rehabilitation strategies are available for mine wastes that produce acid mine drainage (AMD). One of them consists in building a cover with capillary barrier effects (CCBE) on the tailings to limit the availability of oxygen, an essential component of the chemical reactions leading to the generation of AMD. Prior to cover construction, a monitoring strategy must be established to evaluate the response and performance of the cover system. The key parameters to monitor should include matric suction and volumetric water content in the CCBE, oxygen flux (and/or oxygen concentration) through and below the cover, and the main meteorological parameters for the impoundment. In this paper, different techniques available to measure the targeted parameters are described and their main properties are given. Recommendations (based on existing cases) on the location and the number of monitoring stations and on the measurement frequency for each monitored parameter are also proposed.

May 1, 2007